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31.
The criterion tumor volume (TV) for clinically insignificant prostate cancer has been reported, but it differs from study to study: some have reported TV < 200 mm3; others, < 500 mm3. The aim of the present study was to distinguish clinically insignificant cancers from significant ones using molecular biological methods. A total of 184 microscopic cancers (MC) defined as limited within a 3 mm circle and 82 main tumor (MT) nodules were selected. Thirteen microsatellite loci at 6q22, 8p23.2–23, 13q14 and 13q33 were evaluated for loss of heterozygosity (LOH). MT were subgrouped as TV ≥ 500 mm3 or <500 mm3; TV ≥ 200 mm3 or < 200 mm3; and TV < 200 mm3, 200 mm3 ≤ TV < 500 mm3 or TV ≥ 500 mm3; and frequencies of LOH were compared between these three groups. Frequencies of LOH at 6q16–21, 6q22, 8p23.1, 8p23.2, 13q14 were significantly lower in MC (1.0%, 2.7%, 1.9%, 1.1% and 5.4%) than in MT (30.9%, 40.4%, 12%, 8.7% and 20.6%), but no significant differences in LOH frequency were found within each of the three TV groups, between each cut-off. When insignificant tumor is defined as TV < 200 mm3 or < 500 mm3, it should include tumors with malignant potential equivalent to larger tumors. It is suggested that in order to identify insignificant tumor within a strict safety range, TV should be set lower.  相似文献   
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The intracellular adaptor Lnk (also known as SH2B3) regulates cytokine signals that control lymphohematopoiesis, and Lnk?/? mice have expanded B‐cell, megakaryocyte, and hematopoietic stem‐cell populations. Moreover, mutations in the LNK gene are found in patients with myeloproliferative disease, whereas LNK polymorphisms have recently been associated with inflammatory and autoimmune diseases, including celiac disease. Here, we describe a previously unrecognized function of Lnk in the control of inflammatory CD8+ T‐cell proliferation and in intestinal homeostasis. Mature T cells from newly generated Lnk–Venus reporter mice had low but substantial expression of Lnk, whereas Lnk expression was downregulated during homeostatic T‐cell proliferation under lymphopenic conditions. The numbers of CD44hiIFN‐γ+CD8+ effector or memory T cells were found to be increased in Lnk?/? mice, which also exhibited shortening of villi in the small intestine. Lnk?/? CD8+ T cells survived longer in response to stimulation with IL‐15 and proliferated even in nonlymphopenic hosts. Transfer of Lnk?/? CD8+ T cells together with WT CD4+ T cells into Rag2‐deficient mice recapitulated a sign of villous abnormality. Our results reveal a link between Lnk and immune cell‐mediated intestinal tissue destruction.  相似文献   
33.
Primary CNS diffuse large B-cell lymphoma (CNS DLBCL) is confined to the CNS, and constitutes a distinct entity. In the present study a series of 40 Japanese patients with CNS DLBCL who presented with neurological, but not systemic symptoms, was reviewed. Median survival was 18.7 months. CD5, CD10, Bcl-6, MUM-1, and Bcl-2 were positive in 30%, 10%, 84%, 100%, and 93% of patients, respectively. All CD10-negative patients had non-germinal center B-cell type. There was no significant difference in survival among the immunophenotypic subgroups. CNS DLBCL appeared to be homogenous as a group, which prompted the comparison with another distinct extranodal entity, intravascular large B-cell lymphoma (IVLBCL) in Japanese patients. CNS DLBCL patients did not differ in age, sex, or immunophenotype, including CD5 positivity, from IVLBCL patients, but were significantly less likely to have poor prognostic parameters than IVLBCL patients: the international prognostic index score was low or low–intermediate in 86% of CNS DLBCL patients and high or high–intermediate in 98% of IVLBCL patients. Notably, despite this difference, their survival curves almost overlapped. The present study highlights the issue of clinical distinctiveness of aggressive extranodal lymphomas, the peculiar migration and localization of which should be further clarified.  相似文献   
34.
Heme oxygenase-1 (HO-1) is a stress-induced enzyme that catalyses the oxidation of heme to biliverdin. The primary deficiency of this enzyme has been shown in HO-1 knockout mice, and is characterized by intrauterine death and chronic inflammation. The first case of human HO-1 deficiency was reported in 1999. Human HO-1 deficiency has been observed to involve the endothelial cells more severely, resulting in hemolysis and disseminated intravascular coagulation. We report another case of human HO-1 deficiency in a young girl with congenital asplenia, who presented with severe hemolysis, inflammation, nephritis, which was refractory to therapy with corticosteroids, cyclophosphamide, and rituximab.  相似文献   
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In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer.  相似文献   
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The involvement of p53 mutations in prostate cancers in Japan was investigated. To evaluate any possible clinicopathological significance, p53 mutations in 40 samples from 36 Japanese prostate cancers of different stages (five cases of latent tumors, three of stage A cancers, 10 of stage B, five of stage C and 13 of stage D), including four lymph node metastases of stage D cases, were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and sequencing. Mutations were detected in five of 40 samples (12.5%); four were in primary cancers and the other in a lymph node metastasis from one of them. All mutation-positive cases were in stage D, and the mutation frequency in stage D cases was 31%. This result indicates that p53 mutations may play a role in the progression of a subgroup of prostate cancers in Japanese, as observed for Americans and Europeans. However, a difference was noted between Japanese and Americans in the p53 mutational spectrum (at CpG site), presumably arising from variation in the underlying etiotogic factors.  相似文献   
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